Most seem to sell on sites like eBay or Craigslist. As a starting point, you can check Mac2Sell, eBay (including completed sales), and Amazon for prices of similar models, to get an idea of what a reasonable price may be. Then adjust the price to account for condition, configuration, remaining AppleCare coverage (if any), etc. You can also check the Apple refurbished store to see what similar models are selling for.

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